scholarly journals The Effect of UDMA/TEGDMA Mixtures and Bioglass Incorporation on the Mechanical and Physical Properties of Resin and Resin-Based Composite Materials

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Laura C. Nicolae ◽  
Richard M. Shelton ◽  
Paul R. Cooper ◽  
Richard A. Martin ◽  
William M. Palin

Incorporating Bioglass into dental composites may improve biocompatibility and aid tooth and bone tissue remineralisation. This study aimed to determine the impact of Bioglass and silica filler on the mechanical and physical properties of cured photopolymers. Hardness (Vickers microhardness test), flexural strength (FS), and flexural modulus (FM) (three-point bend test) of resins containing various urethane dimethacrylate (UDMA)/triethylene glycol dimethacrylate (TEGDMA) and bisphenol A-glycidyl methacrylate (bisGMA)/TEGDMA concentrations (20–80 mass%) were tested. Degree of conversion (DC), FS, and FM of resin composites containing nonsilanised irregular 45S5-Bioglass (50 μm; 5–40 mass%) and/or silanised silicate glass filler particulates (0.7 μm; 30–70 mass%) were tested. Data was analysed using one-way ANOVA. UDMA/TEGDMA resins exhibited increased hardness and FM compared with bisGMA/TEGDMA resins. Addition of Bioglass particles to 60/40 wt% UDMA/TEGDMA or bisGMA/TEGDMA resins may enable the development of new materials that exhibit higher or at least equivalent values of DC, FS, and FM compared with conventional resin composites.

2012 ◽  
Vol 23 (5) ◽  
pp. 508-514 ◽  
Author(s):  
Vinícius E. S. Gajewski ◽  
Carmem S. Pfeifer ◽  
Nívea R. G. Fróes-Salgado ◽  
Letícia C. C. Boaro ◽  
Roberto R. Braga

The organic phase of resin composites is constituted by dimethacrylate resins, the most common monomers being the bisphenol A diglycidildimethacrylate (BisGMA), its ethoxylated version (BisEMA), triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA). This study compared the homopolymers formed from the monomers used in restorative dental composites in terms of their degree of conversion (DC) and reaction kinetics (by near infra-red spectroscopy, n=3), mechanical properties (flexural modulus and strength in three point-bending, FM and FS, respectively, n=15), water sorption and solubility (WS and SL, respectively - ISO 4049, n=5). Materials were made photopolymerizable by the addition of camphoroquinone/dimethylamine ethyl methacrylate. TEGDMA showed the highest DC, followed by BisEMA, UDMA and BisGMA, both at 10 min and at 24h (p<0.001). UDMA showed the highest rate of polymerization, followed by TEGDMA, BisEMA and BisGMA (H0=13.254, p<0.001). UDMA and TEGDMA presented similar FM, significantly higher (p<0.001) than BisEMA and BisGMA, which in turn present statistically similar values (p>0.001). For FS, UDMA presented the highest value (p<0.001), followed by TEGDMA, then by BisEMA and BisGMA, which were statistically similar (p>0.001). BisGMA showed the highest WS, and TEGDMA and BisEMA the lowest. UDMA was statistically similar to all (H0=16.074, p<0.001). TEGDMA presented the highest SL, followed by UDMA, BisGMA and BisEMA (p<0.001). The tested homopolymers presented different behaviors in terms of polymerization kinetics, flexural properties, water sorption and solubility. Therefore, the use of copolymers is justified in order to obtain high DC and mechanical properties, as well as good resistance to water degradation.


2013 ◽  
Vol 587 ◽  
pp. 215-221 ◽  
Author(s):  
Laura C. Nicolae ◽  
Richard M. Shelton ◽  
Paul R. Cooper ◽  
Richard A. Martin ◽  
William M. Palin

The effect of Bioglass addition on mechanical and physical properties of photoactive UDMA-TEGDMA resin composites Laura Nicolae, William Palin, Richard Shelton, Paul Cooper Aim: To determine the effect of Bioglass incorporation on the polymerisation rate (Rp), degree of conversion (DC), flexural strength and modulus (FS/FM) of light-curable filled resin composites (FRCs). Methods: Experimental photoactive resins containing various UDMA-TEGDMAratios and filled with non-silanised irregular or spherical 45S5-Bioglass (50μm; 5-40mass%) and/or silanised silicate glass filler particulates (0.7μm; 50-70mass%) weretested. Rp and DC wereanalysed by real-time near-infrared spectroscopy. FS/FM of resins and FRCs were determined using three-point flexural strength tests. Results: Addition of up to 20mass%45S5-Bioglass filler significantly increased DC and FS(p<0.05), although >20mass% had deleterious effects on mechanical properties. The addition of spherical Bioglass particles resulted in an increased DC compared with that of irregular filler morphology although no significant differences mechanical properties were observed (p>0.05). Conclusion: Addition of 45S5-Bioglass with specific filler content, size and morphology resulted in enhanced mechanical and physical properties compared with conventional silicate glass FRCs.


2007 ◽  
Vol 37 (5) ◽  
pp. 866-873 ◽  
Author(s):  
Jun Li Shi ◽  
Bernard Riedl ◽  
James Deng ◽  
Alain Cloutier ◽  
S. Y. Zhang

Mechanical and physical properties of medium-density fibreboard (MDF) panels made from black spruce ( Picea mariana (Mill.) BSP) top, middle, and butt logs were studied. The analysis of variance and analysis of covariance were both performed to examine the impact of log position in the tree on panel modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB), linear expansion (LE), thickness swell (TS), and water absorption. Results indicate that MOE and IB strength of MDF panels made from top and middle logs were significantly superior to those of panels made from butt logs; however, there was no significant difference in MOE and IB between panels made from top and middle logs. Water absorptions of top and middle log panels were significantly lower than that of panels made from butt logs, and the difference in water absorption between panels made from top and middle logs was not significant. TS of top log panels was the smallest among the panels from the three log positions in the tree and was significantly different from those of middle and butt log panels. TS of butt log panels was the highest, which was significantly different from that of top and middle log panels. The differences in LE among the panels made from top, middle, and butt logs were not significant. The comparison of MOR of top, middle, and butt log panels was dependent on panel density because of the interactions among the three groups. Top and middle log panels showed superior properties, because the thinner cell walls of fibres from top and middle logs resulted in an increased compaction ratio compared with the butt log panels. Panel density affected both panel MOR and MOE considerably; however, its impact on IB, LE, TS, and water absorption was not significant in this study. The equations describing the linear relationships between MOR, MOE, and panel density were developed.


2005 ◽  
Vol 6 (4) ◽  
pp. 93-100 ◽  
Author(s):  
Thomas R. Meng ◽  
Mark A. Latta

Abstract Resistance to impact fracture and high flexural strength are desirable properties of denture base acrylics. The purpose of this laboratory study was to determine the Izod impact strength, the flexural strength, the flexural modulus, and the yield distance for four premium denture resins. Bar specimens 86 x 11 x 3 mm of Lucitone 199, Fricke Hi-I, ProBase Hot, and Sledgehammer Maxipack were fabricated following the manufacturer's instructions for heat processing. The bars were surface finished using silicon carbide paper to 600 grit. Ten specimens from three lots of each material were made (n=30). Flexural strength, flexural modulus, and yield distance were determined by testing the specimens to failure using a three-point test fixture. Izod impact strength was determined using an Izod tester on un-notched specimens generated from the flexural test (n=60). Analysis of variance (ANOVA) and post-hoc Tukey's test were used for statistical comparison of each property. There were significant differences in the physical properties among the denture acrylics tested. Lucitone 199 demonstrated the highest impact strength, flexural strength, and yield distance (p<0.05). Lucitone 199 with an Izod impact strength of 5.5 ± 1.2 N·m, a flexural strength of 99.5 ± 4.5 MPa, and yield distance of 9.9 ± 0.76 mm exhibited statistically greater results than Fricki Hi-I, ProBase Hot, and Sledgehammer Maxipack. Fricki Hi- I with a yield distance of 7.3 ± 1.1 mm was statically greater than ProBase Hot and Sledgehammer Maxipack. Fricki Hi-I, ProBase Hot, and Sledgehammer Maxipack were statistically similar for the Izod impact strength and flexural strength tests performed. ProBase Hot and Sledgehammer Maxipack yielded statistically similar results for all tests performed. Flexural modulus had an inverse relationship to the impact strength, flexural strength, and yield distance. Citation Meng TR, Latta MA. Physical Properties of Four Acrylic Denture Base Resins. J Contemp Dent Pract 2005 November;(6)4:093-100.


2010 ◽  
Vol 123-125 ◽  
pp. 1139-1142 ◽  
Author(s):  
Sawitri Srisuwan ◽  
Pranee Chumsamrong

In this study, the effects of weave type and fiber content on the physical properties of woven sisal fiber/epoxy composites were investigated. Sisal fibers used in this work were obtained from Nakhon Ratchasima, Thailand. Both untreated and alkali-treated fibers were employed. The woven sisal fibers were manufactured by hand weaving process. The fiber content in sisal fiber/epoxy composites were 3 wt.%, 5 wt.% and 10 wt.%. The composites were cured at room temperatures. In order to determine mechanical properties of the composites, flexural and impact tests were applied. Flexural strength and flexural modulus of all composites were higher than those of pure epoxy resin and tended to increase with increasing fiber content. The impact strength of all composites was lower than that of pure epoxy resin. The composites containing 10 wt.% sisal fibers showed the highest impact strength. There was no definite influence of weave type on flexural properties of the composites. At 3 and 5 wt.% fiber, the composites containing plain weave fibers seemed to show a higher impact strength than the composites containing other weave types.


Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2851
Author(s):  
Harri Junaedi ◽  
Muneer Baig ◽  
Abdulsattar Dawood ◽  
Essam Albahkali ◽  
Abdulhakim Almajid

The effect of various combinations of filler materials on the performance of polypropylene (PP)-based composites was investigated. PP in particulate form was used as the matrix. Milled short carbon fiber (SCF) micro-size, graphite nano-platelet (GNP), and titanium dioxide nanoparticles (nTiO2) were used as fillers. These fillers were incorporated in the polymer matrix to produce mono-filler (PP/SCF and PP/nanofiller) and hybrid composites. Hybrid composites consist of PP/10SCF/GNP, PP/10SCF/nTiO2, and PP/10SCF/GNP/nTiO2. The effect of the addition of SCF, GNP, and nTiO2 on PP-based composites was investigated by analyzing their morphological, mechanical, and physical properties. The addition of mono-filler to the PP matrix improved the mechanical properties of the composites when compared to the neat PP. The ultimate tensile strength (UTS), flexural modulus, flexural strength, and impact toughness of the hybrid composites with 15 wt % total loading of fillers, were higher than that of mono-filler composites with 15 wt % SCF (PP/15SCF). A maximum increase of 20% in the flexural modulus was observed in the hybrid composite with 10 wt % of SCF with the additional of 2.5 wt % GNP and 2.5 wt % nTiO2 when compared to PP/15SCF composite. The addition of 2.5 wt % nTiO2 to the 10 wt % SCF reinforced PP, resulted in increasing the strain at break by 15% when compared to the PP/10SCF composite. A scanning electron microscope image of the PP/10SCF composite with the addition of GNP improved the interfacial bonding between PP and SCF compared with PP/SCF alone. A decrease in the melt flow index (MFI) was observed for all compositions. However, hybrid composites showed a higher decrease in MFI.


2020 ◽  
Vol 21 (14) ◽  
pp. 5136 ◽  
Author(s):  
Håvard J. Haugen ◽  
Danijela Marovic ◽  
Matej Par ◽  
Minh Khai Le Thieu ◽  
Janne E. Reseland ◽  
...  

The aim of the study was to perform comprehensive characterization of two commonly used bulk fill composite materials (SDR Flow (SDR) and Filtek™ Bulk Fill Flowable Restorative (FBF) and one conventional composite material (Tetric EvoCeram; TEC). Eleven parameters were examined: flexural strength (FS), flexural modulus (FM), degree of conversion, depth of cure, polymerisation shrinkage (PS), filler particle morphology, filler mass fraction, Vickers hardness, surface roughness following simulated toothbrush abrasion, monomer elution, and cytotoxic reaction of human gingival fibroblasts, osteoblasts, and cancer cells. The degree of conversion and depth of cure were the highest for SDR, followed by FBF and TEC, but there was no difference in PS between them. FS was higher for bulk fill materials, while their FM and hardness were lower than those of TEC. Surface roughness decreased in the order TEC→SDR→FBF. Bisphenol A-glycidyl methacrylate (BisGMA) and urethane dimethacrylate were found in TEC and FBF eluates, while SDR released BisGMA and triethylene glycol dimethacrylate. Conditioned media accumulated for 24 h from FBF and TEC were cytotoxic to primary human osteoblasts. Compared to the conventional composite, the tested bulk fill materials performed equally or better in most of the tests, except for their hardness, elastic modulus, and biocompatibility with osteoblasts.


2017 ◽  
Vol 11 (1) ◽  
pp. 14-24 ◽  
Author(s):  
Brundaban Patro ◽  
D. Shashidhar ◽  
B. Rajeshwer ◽  
Saroj Kumar Padhi

Background: Due to light weight, high performance and excellent mechanical properties, carbon fibers are considered a key material in the 21st century. These are extensively used in many industries for structural usages, such as aerospace, aeronautical, sporting goods applications, and automotive and medical devices, due to their desirable strength to weight properties. Now, these are globally accepted as a high performance and high-strength material. Most of the carbon fibers are derived from polyacrylonitrile fiber precursor. These materials have the potential for fire hazards caused due to heat, smoke, and electric short circuit. Objective: To prepare polyacrylonitrile carbon and epoxy resin laminates in multilayers by hand-lay-up method and testing by ASTM (American Society for Testing and Materials) standards. Method: Polyacrylonitrile carbon fiber/epoxy resin composites are prepared using the hand-lay-up method. For the non-destructive testing, the ultrasonic type is used. For the destructive testing, a universal testing machine is used to test the tensile test, the flexural test and the inter-laminar shear stress test, as per the ASTM standard. Subsequently, the physical properties, such as the density test and the fiber content, the resin content and the void content tests of the laminate are carried out. Results: The experimental results show that the matrix laminates have good mechanical and physical properties. Conclusion: Preparation and testing of polyacrylonitrile carbon/epoxy resin composites are carried out and the prepared laminates exhibit good mechanical and physical properties. Hence, the laminates can be used in many industrial and commercial applications, as a composite material.


2017 ◽  
Vol 4 (2) ◽  
pp. 157
Author(s):  
M. I. Iskandar

Effect of Temperature of Straw Boiling on Mechanical and Physical Properties of Particle Board          Levels of extractive substances in the straw as much as 10-15% and 12-18% silica content respectively. Two of these substances can inhibit good adhesion bonding between the particles during the sealing process. Treatment of straw boiling  before gluing process can reduce the negative effects of extractive substances to the bonding adhesive. The purpose of this study was to determine the effect of temperature of the boiling straw on mechanical and physical properties of particle board. The tested physical properties included density, moisture content, thickness swelling and water absorption while the mechanical properties tested included flexural modulus, fracture modulus, internal bonding strength and screw holding strength. Analysisof statistic of the data used was Complete Random Design (RAL). The treatment consisted of a five-level with three replications so that the total number of trials was fifteen. To determine the effect of treatment carried out the Analysis of Variance. To determine the effect of treatment was significantly different would do a further test the Duncan's multiple range test. Processing data using SAS software, version 6123. The results showed an increase in the temperature of straw boiling was very significant and fluctuative on the properties of particle board and the moisture content, thickness swelling 24 hours, flexural modulus (MOE), fracture modulus (MOR), but did not significant affect the density and internal bonding strength. Boiling temperature 40⁰C on straw produce panels with the best qualities. The properties of particle board research results that met the requirements of Standard JIS A 5908: 215 only the density and moisture content.Keywords: temperature, boiling, straw, mechanical physical properties ABSTRAK         Kadar zat ekstraktif dalam jerami sebanyak 10-15% dan kadar silika 12-18%. Dua zat tersebut dapat menghambat ikatan rekat yang baik antar partikel pada waktu proses perekatan. Perlakuan perebusan jerami sebelum proses perekatan dapat mengurangi pengaruh negatif zat ekstraktif terhadap ikatan rekat. Tujuan penelitian ini adalah untuk mengetahui pengaruh temperatur perebusan jerami terhadap sifat fisis mekanis papan partikel. Sifat fisis yang diuji meliputi kerapatan, kadar air, pengembangan tebal dan daya serap air sedangkan sifat mekanis yang diuji meliputi modulus lentur, modulus patah, keteguhan rekat internal dan kuat pegang sekrup. Analisis statistik data yang digunakan adalah Rancangan Acak Lengkap (RAL). Perlakuan terdiri dari lima taraf dengan ulangan sebanyak tiga sehingga jumlah total percobaan adalah lima belas. Untuk mengetahui pengaruh dari perlakuan dilakukan analisis ragam (Analysis of Variance). Untuk mengetahui pengaruh berbeda nyata perlakuan dilakukan uji lanjut dengan uji wilayah berganda Duncan. Pengolahan data menggunakan software SAS versi 6.123. Hasil penelitian menunjukkan peningkatan temperatur perebusan jerami berpengaruh sangat nyata dan fluktuatif terhadap sifat-sifat papan partikel dan kadar air, pengembangan tebal 24 jam, modulus lentur (MOE), modulus patah (MOR), tetapi tidak berpengaruh nyata terhadap kerapatan dan keteguhan rekat internal. Perebusan jerami pada suhu 40⁰C menghasilkan panil dengan sifat-sifat terbaik. Sifat-sifat papan partikel hasil penelitian yang memenuhi persyaratan Standar JIS A 5908:215 hanya kerapatan dan kadar air.Kata kunci: temperatur, perebusan, jerami, sifat fisis dan mekanis


2014 ◽  
Vol 592-594 ◽  
pp. 912-916 ◽  
Author(s):  
K. Chandra Shekar ◽  
B. Anjaneya Prasad ◽  
N. Eswara Prasad

The effect of amino multi-walled carbon nanotubes (MWCNTs) on the flexural properties of epoxy/ nanocomposites was studied. Sonication technique was employed for dispersion of amino MWCNTs in epoxy. The properties of both neat epoxy and nanocomposites extensively studied by using three point bend test and scanning electron microscopy. From the experimental results, it was found that reinforcement with carbon nanotubes improved the flexural properties, namely (a) flexural modulus, (b) flexural strength, (c) nonlinear deformation and (d) total flexural toughness.


Sign in / Sign up

Export Citation Format

Share Document